Inspiration
"The dominant activity was alpha waves, indicating a very low level of cortical arousal: a relaxed state, as though the conscious mind was quiet while the brain was making connections behind the scenes. It's the same sort of brain activity as in some stages of sleep, dreaming or rest, which could explain why sleep and relaxation can help people be creative."

Meditation dampens the dominating conscious activity of "working" memory, allowing more data flow between subconscious & conscious. Conscious editing is latent inhibition -- inhibits flow between conscious mind & subconscious. Inspiration comes from the subconscious. Conscious quieting of elaboration is meditation, it is consciously enabling creativity while in a waking state. After a long period of meditation, including any intensely mindful state (walking or eating), Buddhist have a term for the rapture of creativity that follows: dharmamega.

"Strikingly, it was the people who showed the biggest difference in brain activity between the inspiration and development stages who produced the most creative storylines."

It is not possible to fully understand "biggest difference" until one completes a silent meditation retreat. And the affect is proportional to the duration. Completing a 30 day is at least 3 times as intense as a 10 day silent retreat.

"Very creative people move between these states intuitively. Creativity, it seems, is about mental flexibility: perhaps not a two-step process, but a toggling between two states."

Even more interesting is that meditators can toggle more efficiently. Once the path is worn in, traversing it becomes more efficient. Conscious elaboration becomes a well lubricated faucet which is more easily adjusted. Thoughts become more objective and less engulfing, less "who I am" and more a thought that can be released.